WordPress Theme Frameworks provides you with ready to use code library which can be used to develop themes/child themes for your WordPress site in less amount of time. These Frameworks eliminates some of the repetitive work that needs to be done with any custom WordPress Theme.
According to Justin Tadlock, A framework is a solidly coded theme that should serve as a base for other projects.
Some can be extended through the use of child themes. A child theme hooks into its parent (the framework) and uses all of its template files and functions. The child can change both the way the parent theme looks and functions.
Types of WordPress Theme Frameworks
- Base/starter Theme
Drop-in code library framework is not a stand-alone Theme. These type of frameworks cannot be installed nor used as a stand-alone Theme. Rather, these libraries are included with the Theme, and “bootstrapped” to the Theme by being included in the Theme’s functions.php file.
Some examples of Drop-in frameworks include:
- Carrington Core
- Hybrid Core
- Options Framework
- UpThemes Framework
Base/starter” Theme framework is a stand-alone Theme designed to be a flexible foundation for quicker WordPress development, usually serving as a robust Parent Theme for Child Themes. Some Theme frameworks can also make theme development more accessible, removing the need for programming or design knowledge with options pages.
Some examples of such frameworks include:
- WP Framework
- K9 Canvas
There are also other WordPress Theme Frameworks which are not listed here, but I hope this simple information extracted from WordPress codex will help you in getting some knowledge about What is a WordPress Theme Framework.